Nearly half of those surveyed did nothing when they saw illegal fishing.

Even if you're not the one to commit a crime, if you see it happen and don't say anything, that's a problem too. Unfortunately, that's what a majority of fishermen are doing when it comes to illegal poaching.

According to The Conversation, a study conducted by ARC Centre of Excellence for Coral Reef Studies at James Cook University (JCU) found that almost half of the 2,000 surveyed fishermen from seven countries had seen illegal poaching in the last year.

When asked what they did about it, "nothing" was the most common answer.

That's a disheartening response, since wildlife poaching affects all kinds of marine species like turtles, fish, whales, dolphins, sharks, coral and more, according to the World Wildlife Fund.

And marine reserves only protect environments so long as they actually remain untouched. If fishing activity is still going on in those areas, or protected species are being poached, then the ocean doesn't stand a chance to recover from the harm we've already done to it.

Fortunately, all hope may not be lost.

It's important to look at why fishermen aren't reporting, so that their opinions can be changed. When asked why the fishermen ignored the poaching, the most common answer was a desire to stay out of conflict.

And, in the Great Barrier Reef, where JCU reported that almost 80 percent of fishermen ignored poaching, they cited their lack of concern as confusion over what constitutes illegal fishing, a belief that it's not their job to report it, and lack of knowledge on how to report.

All of that can be remedied by countries providing better information to their fishermen. For example, The Conversation reports that there's a Great Barrier Reef hotline where fishers can report illegal activity.

Just give it a call, and then it's out of your hands but not being ignored.

Illegal poaching is a crime, and fishermen should not be expected to take the law into their own hands and confront poachers. But they should feel compelled to call the appropriate authorities and report the information. That's a conflict-free way to help the sea and their fellow fishers.

It's vital because, in some areas of the ocean, fishermen may be the only line of defense against illegal activity. According to an Oceana report, some commercial fishing vessels periodically turn off their Automatic Identification System, which renders them invisible to public tracking systems.

As Lacey Malarky, an illegal fishing analyst for Oceana told Business Insider, this kind of behavior is concerning. "We have no idea what's happening. ... There shouldn't be any questions, especially around these really valuable [marine reserve] areas," she said.

If even one fisher is ignoring the rules, it affects all the fishermen who are abiding by them.